Conventional robotic pool cleaners are powered by electric drive motors and/or water pumps that receive power from a power cord or cable that is attached to a low-voltage power source outside of the pool. The use of a battery or batteries as a power source has also been proposed. For example, a rechargeable battery in a waterproof or water-resistant floating case having a power cable extending to the submerged pool cleaner has the advantage of eliminating or substantially reducing problems associated with twisting of the power cable which occurs with a remote stationary power supply unit as the pool cleaner traverses the bottom of the pool in its cleaning pattern.
Although the inclusion of one or more batteries in the submersible pool cleaner housing has been proposed, the limitations of battery life and power consumption have prevented the realization of a practical commercial pool cleaner having an integral battery as the sole source of power that is required for cleaning a residential swimming pool. As used herein, the term “integral battery” means a battery that is secured to the moving pool cleaner, preferably on the interior of the housing, and is to be distinguished from a battery that is tethered to the moving pool cleaner as by a power cable extending away from the pool cleaner to a floating battery housing, or an otherwise remotely positioned battery.
As previously proposed, an integral battery lacks sufficient power to complete cleaning patterns known to have been disclosed or used by the prior art. Furthermore, while a floating battery has some apparent advantages, battery power is required to overcome hydrodynamic forces resulting from moving the battery housing through the water by the tethering power cord.
A robotic pool cleaner utilizes one water pump assembly to draw water through an internal filter. The pool cleaner can also have at least one drive motor that is utilized to move the cleaner across the surface(s) to be cleaned. Typically, the drive motor that is linked through mechanical drive means has a relatively lower power consumption, as compared to the power consumed by the pump motor.
The motion of the pool cleaner can be directed from the motor through a drive train to a generally cylindrical cleaning brush which contacts the surface of the pool to be cleaned or to a rotating axle that causes the movement of one or more wheels or endless tracks which support the pool cleaner. A jet of water can also be discharged from a port at approximately a right angle to the surface over which the pool cleaner is moving in order to maintain the pool cleaner, which is conventionally of nearly neutral buoyancy, in the appropriate orientation for cleaning.
As will be understood by one of ordinary skill in the art, the pool cleaner can also be powered by a jet of water that is alternatively discharged in opposing directions that are generally parallel to the surface being cleaned to cause the cleaner to move first in one direction and then in the opposite direction. With this arrangement, it is possible to eliminate the drive motor and drive assembly, thereby reducing the overall power consumption of the pool cleaner.
It is also well known in the art to provide the pool cleaner with a pre-programmed microprocessor and electronic control device, which can include a controller and memory device that is wired to one or more electronic and/or electro-mechanical switches, sensors and the like, in order to insure that the pool cleaner follows a pattern that provides for the cleaning of the entire bottom surface of the pool. In some cases, the programmed movement is entirely random and can take account of pools of different sizes and shapes. Other pool cleaner control devices are based upon the initial orientation of the cleaner after it encounters a sidewall of a rectilinear pool having no obstacles or accessories that might impede or trap the pool cleaner, or otherwise interfere with a regular transverse repetitive movement that is designed to pass the cleaner over the entire bottom surface of the pool.
It is therefore an object of the present invention to provide an improved swimming pool cleaner having an integral battery that is capable of cleaning an entire swimming pool without recharging.
It is a further object of the invention to provide a robotic swimming pool cleaner having an integral battery and no external wires or connections leading to accessories outside of the pool.
Another object of the invention is to provide an automatic program controlled robotic pool cleaner that is powered by an integral battery that is simple and economical in its construction and which can complete the cleaning of the bottom surface of the residential pools without interruption or recharging of the integral battery during the cleaning operation.
It is a further object of the invention to provide an improved programmed electronic integrated circuit device that provides for an efficient pattern of movement for a pool cleaner having an integral battery during the cleaning of the bottom surface of a swimming pool.